#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; #define ll long long #define ld long double #define EPS 0.0000000001 #define INF 1e9 #define MOD 1000000007 #define rep(i,n) for(i=0;i vi; typedef pair pii; signed main(void) { int i,j; int n; cin>>n; vi a(n); rep(i,n)cin>>a[i]; vi dp1(n),dp2(n); dp1[0]=dp2[0]=a[0]; for(i=1;i